We were so excited about that and his genius touched so many generations. Rank limitless, versatility through comedy and drama. He got his first big break on "Happy days," 1978. Look at this appearing -- he'll take Richie Cunningham back with him and breakout role in "Mork & Mindy" and Chris Connelly has a look back at this unique career. Reporter: He began in the 1970s as the most relentlessly funny comedian of the age. Jokes impressions and insights. Flipping now. I'm melting. Help me. Help me. Reporter: The sitcom "Mork & Mindy" became a showcase for his quick silver wit and dazzled on television and talk shows. I told you, I saw it first. Reporter: Soon the movies would utilize his rapid-fire always switched on skills. An armed forces radio deejay in 1987's "Good morning, Vietnam." The voice of the genie in the animated hit "Aladdin." 10,000 years will give you such a crick in the neck. Reporter: And massacre raiding as a british nanny in "Mrs. Doubtfire." Hello com. Yet he was more than a funny man. Robin Williams would make his greatest mark on the movies playing characters of compassion as a teacher in "Dead poets society." We must constantly look at things in a different way. Reporter: As a doctor looking after children in "Patch Adams" and as a therapist counseling Matt Damon's math student in "Good will hunting." You don't know about real loss because it only happens when you love something more than yourself. Reporter: For which he would win a supporting actor Oscar. This might be the one time I'm speechless. Reporter: Leads others to hope in the wake of despair he did that in real life too entering the hospital room of his classmate Christopher reeve after the depth that paralyzed him. He worked alongside whoopi Goldberg and Billy crystal for the charity comic relief and on the 9/11 tribute. More recently he played darker obsessive roles in "One hour photo." Last year he starred on "The crazy ones," his first sitcom since "Mork & Mindy" and reunited with his old co-star Pam Dawber. You're like an alien. Reporter: For the millions delighted by his inexhaustible comic gift or moved by his wellspring of deep feeling that Williams voice has been stilled forever is an occasion for sadness and tribute. Thank you, boys. Thank you. This is not a farewell anyone wanted to see because no performer was ever more generous with his comic gift than he was. David? All right, Chris Connelly, our thanks to you.

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